Upholder had six bow-mounted weapon discharge tubes, no longer called torpedo tubes because they would also be used to launch sub-surface missiles. She was fitted with a positive air turbine pump discharge system capable of firing a total of 18 dual-purpose wire-guided Tigerfish heavyweight torpedoes or Sub-Harpoon encapsulated anti-ship missiles, or mines. The traditional Torpedo Stowage Compartment (TSC) was now termed the Weapon Stowage Compartment (WSC).
A fully- integrated computerised sonar suite provided Upholder with long-range detection and attack capability. Information from the sensors was digitally processed and passed by link to a central Action Information Organisation (AIO) computer where it was displayed in coherent form for the Command Team. The Command System also processed visual data from the
